HeadPump#

module wntr.network.elements

class HeadPump[source]#

Bases: Pump

Head pump class, inherited from Pump.

This type of pump uses a pump curve (see curves). The curve is set using the pump_curve_name attribute. The curve itself can be accessed using the get_pump_curve() method.

Constructor

This class is intended to be instantiated through the add_pump method. Direct creation through the constructor is highly discouraged.

Parameters:

name (string) – Name of the pump
start_node_name (string) – Name of the start node
end_node_name (string) – Name of the end node
wn (WaterNetworkModel) – The water network model this pump will belong to.

Attributes

`name`	The link name (read-only)
`link_type`	`"Pump"` (read only)
`start_node`	The start node object.
`start_node_name`	The name of the start node (read only)
`end_node`	The end node object.
`end_node_name`	The name of the end node (read only)
`base_speed`	base multiplier for a speed timeseries
`speed_pattern_name`	pattern name for the speed
`speed_timeseries`	timeseries of speed values (retrieve only)
`initial_status`	The initial status (Opened, Closed, Active) of the Link
`initial_setting`	The initial setting for the link (if Active)
`pump_type`	`"HEAD"` (read only)
`pump_curve_name`	the pump curve name
`efficiency`	pump efficiency
`energy_price`	energy price surcharge (only used by EPANET)
`energy_pattern`	energy pattern name
`vertices`	A list of curve points, in the direction of start node to end node.
`tag`	A tag or label for this link

Read-only simulation results

`flow`	(read-only) current simulated flow through the link
`headloss`	(read-only) current simulated headloss
`velocity`	(read-only) current simulated velocity through the link
`quality`	(read-only) current simulated average link quality
`status`	the current status of the pump
`setting`	Alias to speed for consistency with other link types

__init__(name, start_node_name, end_node_name, wn)#

add_outage(wn, start_time, end_time=None, priority=6, add_after_outage_rule=False)#

Add a pump outage rule to the water network model.

Parameters:

model (WaterNetworkModel) – The water network model this outage will belong to.
start_time (int) – The time at which the outage starts.
end_time (int) – The time at which the outage stops.
priority (int) – The outage rule priority, default = 6 (very high)
add_after_outage_rule (bool) – Flag indicating if a rule is added to open the pump after the outage. Pump status after the outage is generally defined by existing controls/rules in the water network model. For example, the pump opens based on the level of a specific tank.

get_design_flow()[source]#: Returns the design flow value for the pump. Equals to the first point on the pump curve.

get_head_curve_coefficients()[source]#

Returns the A, B, C coefficients pump curves.

For a single point curve, the coefficients are generated according to the following equation:

\(A = 4/3 * H\)

\(B = 1/3 * H/Q^2\)

\(C = 2\)
For a two point curve, C is set to 1 and a straight line is fit between the points.
For three point and multi-point curves, the coefficients are generated using scipy.optimize.curve_fit with the following equation:

\(H = A - B*Q^C\)

Returns:

Tuple of pump curve coefficient (A, B, C). All floats.
The coefficients are only calculated the first time this function
is called for a given HeadPump

get_pump_curve()[source]#

Get the pump curve object

Returns:: the head curve for this pump
Return type:: Curve

remove_outage(wn)#

Remove an outage control from the water network model

Parameters:: wn (WaterNetworkModel) – Water network model

to_dict()#: Dictionary representation of the link

to_ref()#

property base_speed#

base multiplier for a speed timeseries

Type:: float

property efficiency#

pump efficiency

Type:: Curve

property end_node#

The end node object.

Type:: Node

property end_node_name#

The name of the end node (read only)

Type:: str

property energy_pattern#

energy pattern name

Type:: str

property energy_price#

energy price surcharge (only used by EPANET)

Type:: float

property flow#

(read-only) current simulated flow through the link

Type:: float

property headloss#

(read-only) current simulated headloss

Type:: float

property initial_setting#

The initial setting for the link (if Active)

Type:: float

property initial_status#

The initial status (Opened, Closed, Active) of the Link

Type:: LinkStatus

property link_type#

"Pump" (read only)

Type:: str

property name#

The link name (read-only)

Type:: str

property pump_curve_name#

the pump curve name

Type:: str

property pump_type#

"HEAD" (read only)

Type:: str

property quality#

(read-only) current simulated average link quality

Type:: float

property setting#: Alias to speed for consistency with other link types

property speed_pattern_name#

pattern name for the speed

Type:: str

property speed_timeseries#

timeseries of speed values (retrieve only)

Type:: TimeSeries

property start_node#

The start node object.

Type:: Node

property start_node_name#

The name of the start node (read only)

Type:: str

property status#

the current status of the pump

Type:: LinkStatus

property tag#

A tag or label for this link

Type:: str

property velocity#

(read-only) current simulated velocity through the link

Type:: float

property vertices#

A list of curve points, in the direction of start node to end node.

The vertices should be listed as a list of (x,y) tuples when setting.